Wasn't sure where to post this but what are some quality trigger pull gauges? Not sure if I want a digital or spring gauge or other for testing the poundage on triggers?

I'm happy with a Lyman digital and a Wheeler analog. Both work fine.

Most important thing to consider - mount the gun rigid and use a lever to pull the gauge. Dead ending hard against the trigger stop will give artificially high readings. For some of the digitals, if you stop increasing pressure mid stroke, for example, in the middle of a DA revolver or pistol stroke, it'll stall at that number and won't register the true maximum weight. More about holding your tongue just right than the tools themselves.

Somebody smarter than me told me you just need some string and an empty gallon water jug. Mount the gun, secure the string to the trigger, and hang the jug from the string. Slowly, carefully pour water into the jug until the trigger clicks. Then weigh the jug to get the poundage of the trigger pull. Any reason this would not work?

In theory, I see no reason why not. Continual water flow and the ability to stop immediately upon trigger break may lead to false results. 8.34 pounds per gallon of water.

I suspect you could perform numerous rough tests to narrow down a weight range. Then start slightly below needed amount and slowly add water.

Obviously, one would have to mount the weapon pointing upward and make sure string holding jug is not in contact with the stock, handle, or butt.

I have a RCBS analog gage and it has always worked great for me.